μ<Subscript>2</Subscript>-Oxobis[(aroxo)tris(<Emphasis Type="Italic">para</Emphasis>-tolyl)antimony]: Synthesis and Structure

µ₂-Oxobis[(2,4,6-tribromophenoxo)tris(para-tolyl)antimony] (I), µ₂-oxobis[(2,3,4,5,6-pentachlorophenoxo) tris(para-tolyl)antimony] (II), and µ₂-oxobis(2,4-dinitrophenoxo)tris(para-tolyl)antimony] (III) have been synthesized with high yields by the reaction of tris(para-tolyl)antimony with 2,4,6-tribromo-, 2,3,4,5,6-pentachloro-, and 2,4-dinitrophenol, respectively, in ether in the presence of tert-butylhydroperoxide. The Sb atoms in complexes I, II, and III have a distorted trigonal bipyramidal coordination with the aroxyl ligands and the bridging oxygen atom in axial positions. The central Sb–O–Sb moiety in molecules of complexes I–III has an angular structure.     

Tri(<Emphasis Type="Italic">meta</Emphasis>-tolyl)antimony chloro(benzenesulfonate): synthesis and structure

Tri(meta-tolyl)antimony chloro(benzenesulfonate) (I) has been synthesized by the reaction between tri(meta-tolyl)antimony bis(benzenesulfonate) and tri(meta-tolyl)antimony dichloride (toluene; 0.5 h, 100°C). According to X-ray diffraction data, the antimony atoms in two crystallographically independent molecules Ia and Ib have a distorted trigonal bipyramidal coordination to chlorine and oxygen atoms in axial positions: OSbCl, 177.8(4)° (Ia), 178.6(4)° (Ib); CSbC, 114.0(9)°?127.6(8)° (Ia), CSbC, 114.4(8)°?128.0(8)° (Ib); Sb?C, 2.01(2)?2.139(18) Å, Sb?Cl, 2.453(7) Å, Sb?O, 2.163(13) Å (Ia), Sb?C, 2.07(2)?2.14(2) Å, Sb?Cl, 2.442(7) Å; Sb?O, 2.187(14) Å (Ib).     

Crystal Structure of <Emphasis Type="Italic">DL</Emphasis>-Valinium Tetrafluoroantimonate(III) Monohydrate

The crystal structure of an antimony(III) fluoride complex of the composition (C₅H₁₂NO₂)SbF₄·H₂O (I) involving a cation of α-amino isovaleric acid (DL-valine, Val) is determined. Crystals are monoclinic: a = 12.2024(2) Å, b = 6.1636(1) Å, c = 15.5167(3) Å, Z = 4, space group P2₁/c. The structure is formed of DL-valinium (C₅H₁₂NO₂)⁺ cations, complex [SbF₄]_n^n? anions having a polymeric chain structure, and crystallization water molecules. The [SbF₄]_n^n? complex anions consist of trigonal SbF4E bipyramids joined together by asymmetric bridging Sb–F(3)···Sb bonds. The structural units are organized into a threedimensional framework via N–H···F, N–H···O, and O–H···F hydrogen bonds.     

Syntheses and structures of tris(<Emphasis Type="Italic">para</Emphasis>-tolyl)-, tris(3-fluorophenyl)-, and tris(4-fluorophenyl)antimony dioximates

Tris(para-tolyl)antimony bis(2-oxybenzaldoximate) (I), tris(para-tolyl)antimony bis(2-nitrobenzaldoximate) (II), tris(para-tolyl)antimony bis(2-bromobenzaldoximate) (III), tris(3-fluorophenyl)antimony bis(2-oxybenzaldoximate) (IV), tris(4-fluorophenyl)antimony bis(2-bromobenzaldoximate) (V), and tris(4-fluorophenyl)antimony bis(2-nitrobenzaldoximate) (VI) are synthesized by the reactions of tris(paratolyl)-, tris(3-fluorophenyl)-, and tris(4-fluorophenyl)antimony with 2-oxy-, 2-nitro-, and 2-bromobenzaldoxime in diethyl ether in the presence of tert-butyl hydroperoxide. The Sb atoms in complexes I–VI have a distorted trigonal bipyramidal coordination mode with the oximate ligands in the axial positions. CIF files CCDC nos. 1062231 (I), 1059962 (II), 1465384 (III), 1465109 (IV), 1471948 (V), and 1060387 (VI).     

Synthesis and structure of tri-<Emphasis Type="Italic">m</Emphasis>-tolylantimony bis(1-adamantanecarboxylate)

Tri(m-tolyl)antimony bis(1-adamantanecarboxylate) (3-MeC₆H₄)₃Sb[OC(O)C₁₀H₁₅]₂ has been synthesized with a yield of 90.0% by the reaction of tri(m-tolyl)antimony with 1-adamantanecarboxylic acid in the presence of hydrogen peroxide in ether. According to X-ray diffraction analysis data, the antimony atom has a distorted trigonal-bipyramidal coordination with the axially positioned oxygen atoms of carboxyl groups. The axial OSbO angle is 173.1(2)°; the equatorial CSbC angles are 112.0(1)°, 112.0(1)°, and 136.0(3)°; the Sb-O distance is 2.109(3)Å; the Sb-C distances are 2.103(5), 2.103(5), and 2.121(7) Å; intramolecular Sb…O(=C) contacts are 3.069(5) Å.     

Synthesis and structure of bis(1,2-diaminoethane) copper(II) bis(<Emphasis Type="Italic">o</Emphasis>-hydroxybenzoate) monohydrate and <Emphasis Type="Italic">trans</Emphasis>-diaquabis(1,2-diaminoethane)copper(II) bis(<Emphasis Type="Italic">o</Emphasis>-aminobenzoate)

X-ray structural analysis has been performed for two complex compounds: Cu(en)₂(o-HB)₂H₂O (I) (a = 16.873(4) Å, b = 8.713(2) Å, c = 14.803(3) Å, β = 91.15(2)°, V = 2175.8(8) ų, C2/c, Z = 4, R(F) = 0.0263, 1516 reflections with I > 3σ (I)) and [Cu(en)₂(OH₂)₂]²⁺(o-AB^?)₂ (II) (a = 7.488(5) Å, b = 22.122(8) Å, c = 7.856(5) Å, β = 118.77(2)°, V = 1140.7(11) ų, P2₁/n, Z = 2, R(F) = 0.0432, 1684 reflections with I > 3σ(I)) synthesized under identical conditions (en is ethylenediamine, o-HB is o-hydroxybenzoate, and o-AB is o-aminobenzoate). Although the compounds were assumed to have similar structures and the Cu-Lig bond lengths and the cis and trans angles are acceptable for an octahedral structure, the geometric parameters of o-HB suggest that the copper atom has a plane square environment.     

Synthesis,structure, and antibacterial properties of ternary rare-earth complexes with <Emphasis Type="Italic">o</Emphasis>-methylbenzoic Acid and 1,10-phenanthroline

Ternary rare-earth complexes with o-methylbenzoic acid (o-MBA) and 1,10-phenanthroline (Phen) Ln₂(o-MBA)₆(Phen)₂ · nH₂O(n = 0, 1) (Ln = La, Pr, Y, Yb) were synthesized and characterized by elemental analysis, IR, X-ray diffraction, and TG-DTG means. The complex La₂(o-MBA)₆(Phen)₂ · H₂O (I) is composed of two species of binuclear molecules in which the La³⁺ ion is coordinated with two nitrogen atoms of Phen and seven oxygen atoms of carboxylate groups. The carboxylate groups were bonded to La³⁺ in three modes: chelating-bidentate, bridging-bidentate, and chelating-bridging tridentate. The La³⁺ ion adopted a vigorous distorted monocapped square antiprism geometry. Complex I belongs to the triclinic crystal system, P space group, lattice parameters: a = 13.058(3), b = 12.7584(11), c = 20.773(4) Å, α = 101.18(3)°, β = 93.88(3)°, γ = 115.82(3)°, V = 3283.0(11)ų, Z = 2, ρ_calcd = 1.484 mg/m³, M _r = 1467.06, F(000) = 1476, μ = 1.350 mm^-1. The structure was refined to R _l = 0.0631 and wR ₂ = 0.1504. The antibacterial activity test indicates that these complexes exhibit better antibacterial ability against Escherichia coli and Staphylococcus aureus than the corresponding rare-earth chloride or o-MBA.     

Synthesis and crystal structure of (<Emphasis Type="Italic">o</Emphasis>-Diaminobenzene)<Subscript>2</Subscript> Zn(OAc)<Subscript>2</Subscript>

The treatment of o-diaminobenzene with Zn ( OAc )₂ · 2H₂O in alcohol results in the formation of mononuclear bis(o-diaminobenzene)diacetate Zinc, Zn[C₈H₁₁N₂O₂]₂. Its structure was determined by X-ray diffraction analysis. The complex is also characterized by elemental analysis, ¹H NMR and IR. The crystal is monoclinic space group C2, parameters: a = 16.297(5), b = 4.775(3), c = 11.664(5) Å, β = 97.646(5)°, λ = 1.54184 Å, V = 899.6(7) ų, Z = 2, ρ _c = 1.476 g/cm³, M _r = 399.75, F(000) = 416.0, R ₁ = 0.0594, wR ₂ = 0.1439 for 995 observed reflections with I > 2σ(I).     

Aggregation in isomeric imides: analysis of the weak interactions in six <Emphasis Type="Italic">N</Emphasis>-(benzoyl)-<Emphasis Type="Italic">N</Emphasis>-(2-pyridyl)benzamides

Crystal structures of 4-chloro-N-(4-chlorobenzoyl)-N-(2-pyridyl)benzamide (I) Clpod, 3-chloro-N-(3-chlorobenzoyl)-N-(2-pyridyl)benzamide (II) Clmod and 2-chloro-N-(2-chlorobenzoyl)-N-(2-pyridyl)benzamide (III) Clood together with three methylated analogues, Mpod, Mmod and Mood, are presented herein. The Clxod acyclic imides are produced from reacting the 4-/3-/2-chlorobenzoyl chlorides (Clx) with 2-aminopyridine (o), respectively, together with their benzamide analogues Clxo; the Mxod/Mxo triad are produced similarly and in good yield. The five Clxod, Mpod and Mmod structures adopt the open transoid conformations as expected, but Mood crystallises with cisoid oriented benzoyl groups, and this conformation was unexpected, though not unknown. Halogen bonding contacts and weak hydrogen bonding C-H···N/O/π contacts are noted in the structures lacking strong hydrogen bonding donor atoms/groups but possessing a variety of strong and weaker acceptor atoms/groups. For Clxod, contact studies show that both hydrogen and carbon account for a high percentage of elements (70–75%) on the molecular surface and being the most abundant have C···H forming 26–30% of the contacts. Contact enrichment ratios are an indicator of the likelihood of chemical species to form intermolecular interactions with themselves and other species. The C-H···N and C-H···O are the most enriched (with E_HN?>?2.15), indicating that these weak hydrogen bonds are the driving force in the Clxod crystal packing formation. For Mxod, the C···H contact type at 40–52% is the most abundant contact type and C-H···O and C-H···N weak hydrogen bonds dominate with enrichment values in the 1.48–1.78 range. In Mxod, N/O···N/O contacts are effectively absent, except for Mpod (0.2%, N···N contacts) and both H···H and C···C non-polar contacts are moderately impoverished while the C···H interactions are slightly enriched (E?=?1.1–1.21).     

Electron density distribution in crystals of the antimony(V) spiroendoperoxide complexes

The experimental and theoretical electron densities in complexes [6-(2,6-di-iso-propylphenyl)imino-2,4-di-tert-butylcyclohexa-2,4-diene-1-peroxo-1-olato-N,O,O′]tris(p-chlorophenyl)antimony(V), (p-Cl–C₆H₄)₃Sb(2,6-iso-Pr–Ph–AP) · O₂ (I), and [6-(2,6-dimethylphenyl)imino-2,4-di-tert-butylcyclohexa-2,4-diene-1-peroxo-1-olato-N,O,O′]tris(p-chlorophenyl)antimony(V), (p-Cl–C₆H₄)₃Sb(2,6-Me–Ph–AP) · O₂ (II), where AP is 4,6-di-tert-butyl-N-o-iminobenzoquinone dianion, are studied on the basis of high-resolution X-ray diffraction data and theoretical calculations using the density functional theory (B3LYP/DGDZVP). The nature of chemical bonds and the charge distribution on atoms are studied, and the energy of molecular oxygen addition to the Sb(V) o-aminophenolate complexes is estimated. The structures are deposited with the Cambridge Crystallographic Data Centre (CIF files CCDC nos. 1560600 (spherical refinement) and 1560601 (multipole refinement) for complex I; 1560602 (spherical) and 1560603 (multipole) for complex II).     

Tris(<Emphasis Type="Italic">para</Emphasis>-tolyl)- and tris(4-fluorophenyl)antimony diaroxides: syntheses and structures

Bis(4-bromophenoxy)tris(para-tolyl)antimony (I), bis(4-nitrophenoxy)tris(para-tolyl)antimony (II), bis(4-nitrophenoxy)tris(4-fluorophenyl)antimony (III), bis(2,3,4,5,6-pentafluorophenoxy)tris(4-fluorophenyl) antimony (IV), and bis(2,3,4,5,6-pentachlorophenoxy)tris(4-fluorophenyl)antimony (V) (CIF files CCDC 1470829 (I), 1474589 (II), 1062337 (III), 1470476 (IV), and 1472954 (V)) are synthesized in high yields by the reactions of tris(para-tolyl)- and tris(4-fluorophenyl)antimony with 4-bromo-, 4-nitro-, 2,3,4,5,6-pentafluoro-, and 2,3,4,5,6-pentachlorophenol, respectively, in diethyl ether in the presence of tert-butyl hydroperoxide. The Sb atoms in compounds I–V have a distorted trigonal bipyramidal coordination with the aroxy groups in the axial positions (angles OSbO 174.08(11)°–179.4(5)°). The average Sb–C bond lengths in compounds I–V are similar and independent of the nature of the para-substituent in the aryl rings. The Sb–O distances are close to the sum of covalent radii of Sb and O atoms. Hydrogen bonds H···F are involved in the formation of the crystal structures of compounds III–V.     

Synthesis of oxo derivatives of <Emphasis Type="Italic">N</Emphasis>-(<Emphasis Type="Italic">p</Emphasis>-tolysulfonyl)hexahydrocycloalka[<Emphasis Type="Italic">b</Emphasis>]indoles

Hydroxymercuration-demercuration of N-p-tolysulfonyl-4,4a,9,9a-tetrahydro-3H-carbazoles and N-p-tolyl(or methyl)sulfonyl-1,3a,4,8b-tetrahydrocyclopenta[b]indoles leads to the formation of the corresponding N-p-tolylsulfonyl-2,3,4,4a,9,9a-hexahydro-1H-carbazol-2-ols and N-p-tolyl(or methyl)sulfonyl-1,2,3,3a,4,8b-hexahydrocyclopenta[b]indol-2-ols. The latter are oxidized to 2-oxo derivatives with potassium dichromate. The oxidation of 2-methoxy-8-methyl-N-p-tolylsulfonyl-2,3,4,4a,9,9a-hexahydro-1H-carbazol-1-ol under analogous conditions gives 2-methoxy-8-methyl-N-p-tolysulfonyl-2,3,4,4a,9,9a-hexahydro-1H-carbazol-1-one.     

Electrophilic heterocyclization of 6-alken(yn)ylsulfanyl-pyrazolo[3,4-<Emphasis Type="Italic">d</Emphasis>]pyrimidin-4(5<Emphasis Type="Italic">H</Emphasis>)-ones

6-Allylsulfanyl-1-arylpyrazolo[3,4-d]pyrimidin-4(5H)-ones react with iodine and sulfuric acid to give angular pyrazolothiazolopyrimidine derivatives. The reaction of 6-(prop-2-yn-1-ylsulfanyl)-1-(4-tolyl)-pyrazolo[3,4-d]pyrimidin-4(5H)-one with sulfuric acid gives angularly fused pyrazolo[4,3-e][1,3]thiazolo-[3,2-a]pyrimidin-4-one, whereas in the reaction with sodium methoxide linearly fused pyrazolo[3,4-d][1,3]-thiazolo[3,2-a]pyrimidin-4-one was formed. Linearly fused pyrazolo[3′,4′:4,5]pyrimido[2,1-b][1,3]thiazole derivatives were also obtained by reaction of 1-aryl-6-(3-phenylprop-2-en-1-ylsulfanyl)pyrazolo[3,4-d]pyrimidin-4(5H)-ones with sulfuric acid.     

Synthesis and biologic activity of aryloxyaminopropanoles based on substituted <Emphasis Type="Italic">p</Emphasis>-tolylalkylamines

Reaction of 2,2-dimethyl-2-(p-tolyl)ethyl-, 1-p-tolylcyclopenthylmethyl- and 4-(p-tolyl)tetrahydro-2Н-pyran-4-ylmethylamines with phenoxymethyloxiranes substituted in the aromatic ring afforded new aryloxypropanolamines, some of which show moderate adrenoblocking activity.     

Oxidation of 4-nitro-<Emphasis Type="Italic">o</Emphasis>-xylene with nitric acid using <Emphasis Type="Italic">N</Emphasis>-hydroxyphthalimide under phase transfer conditions

4-Nitro-o-xylene was selectively oxidized to 2-methyl-4-nitrobenzoic acid using dilute nitric acid as the oxidizing agent under atmospheric pressure. The oxidation of 4-nitro-o-xylene was effectively promoted by an addition of radical initiators. Under reflux, 2-methyl-4-nitrobenzoic acid was afforded in high yield using nitric acid combined with N-hydroxyphthalimide, cobalt dichloride (CoCl₂ · 6H₂O), manganese acetate (Mn(OAc)₂ · 4H₂O) and phase transfer catalyst.     

Hydrolysis of coordinated aminoacetonitrile in a platinum(IV) complex. Crystal structure of [PtPy(NH<Subscript>2</Subscript>CH<Subscript>2</Subscript>COO)Cl<Subscript>3</Subscript>]

Heating of a hydrochloric acid solution of trans-PtPy(NH₂CH₂CN)Cl₄ results in the hydrolysis of coordinated aminoacetonitrile to aminoacetic acid with the formation of a five-membered chelate ring attached to platinum through the nitrogen atom of the amino group and the oxygen atom of the carboxy group. X-ray diffraction analysis of [PtPy(NH₂CH₂COO)Cl₃] is carried out. The crystals are monoclinic: space group C2/c, a = 21.704(2), b = 8.7027(7), c = 15.576(1) Å, β = 126.606(1)^o, V = 2361.8(3) ų, Z = 8; R _hkl = 0.057, wR = 0.141. In the neutral complex, the Pt atom has a distorted octahedral coordination. The equatorial plane is formed by a Cl atom (Pt-Cl, 2.284(3) Å), the N atom of the Py molecule (Pt-N, 2.062(8) Å), and the N and O atoms of the bidentate-chelating ligand (Pt-N, 2.039(8); Pt-O, 2.026(7) Å); two Cl atoms are arranged in the apical positions (Pt-Cl, 2.301(3) and 2.312(3) Å). The five-membered chelate ring has a flattened gauche conformation with an NCCO torsion angle of 19(1)°.     

Synthesis and structure of tris(4-<Emphasis Type="Italic">N,N</Emphasis>-dimethylaminophenyl)antimony bis(4-methyl benzoate)

The tris(4-N,N-dimethylaminophenyl)antimony bis(4-methyl benzoate) (I) was synthesized by the reaction of tris(4-N,N-dimethylaminophenyl)antimony with 4-methylbenzoic acid in ether in the presence of hydrogen peroxide. According to the X-ray diffraction data, in this molecule the antimony atom is in distorted trigonal-bipyramidal coordination (the axial angle OSbO is 176.15(4)°). The CSbC angles in the equatorial plane are 105.27(6)°, 108.01(6)°, 146.71(6)° (the sum is 359.99°). The Sb-O and Sb-C bond lengths are 2.131(1), 2.137(1) Å and 2.099(2), 2.100(1), 2.107(1) Å, respectively. The intramolecular contacts Sb...O=C are 2.826(1) and 2.928(1) Å.     

Syntheses,crystal structures and in vitro anticancer activities of oxovanadium(IV) complexes of amino acid Schiff base and 1,10-phenanthroline ligands

Four oxovanadium(IV) complexes, namely [VO(desa-met)(phen)]·MeOH·2H₂O (1) (desa-met = Schiff base derived from 4-(diethylamino)salicylaldehyde and dl-methionine, phen = 1,10-phenanthroline), [VO(o-van-met) (phen)]·MeOH·CH₂Cl₂·3H₂O (2) (o-van-met = Schiff base derived from o-vanillin and dl-methionine), [VO(dtbs-napa)(phen)]·2H₂O (3) (dtbs-napa = Schiff base derived from 3,5-di-tert-butyl salicylaldehyde and 3-(1-naphthyl)-l-alanine) and [VO(hyna-napa)(phen)]·1.5H₂O (4) (hyna-napa = Schiff base derived from 2-hydroxy-1-naphthaldehyde and 3-(1-naphthyl)-l-alanine), were synthesized and characterized by IR, HRMS, UV–vis spectra, molar conductance and single-crystal X-ray diffraction (XRD). X-ray structural analysis showed that the V(IV) atoms in all four complexes are six-coordinated in a distorted octahedral environment. In the crystals of complexes 1 and 2, π–π stacking interactions together with hydrogen bonds connect the molecular units into 2D networks. Meanwhile, CH–π stacking interactions are observed between the aromatic rings in the crystals of 1 and 4, while the π–π stacking interactions between aromatic rings in the crystals of 2 and 3 are arranged with a face-to-face mode. The in vitro anticancer activities of these complexes against A-549 and HeGp2 cells were tested by MTT assay.     

Synthesis and crystal structure of <Emphasis Type="Italic">N,N</Emphasis>-dimethylbiguanidinium hexafluorosilicate

The complex [(CH₃)₂NC(NH₂)NHC(NH₂)NH₂]SiF₆ (I) was synthesized and its structure was determined by X-ray crystallography. The crystals are monoclinic: a = 7.4346(10) Å, b = 12.7628(10) Å, c = 11.0828(10) Å, β 104.080(10)°, V = 1020.01(18) ų, ρ_calc = 1.780 g/cm³, μ(MoK _α) = 0.302 mm^?1, Z = 4, space group P2₁/c. The crystals of I are composed of SiF ₆ ^2? anions (Si-F, 1.657(2)–1.699(2) Å) and N,N-dimethylbiguanidinium (H₂L²⁺) cations combined in a framework by interionic H-bonds NH···F. In the cations, protonation sites are the terminal imide groups.     

Molecular and crystal structure of 15-acetylsongorine and songoramine isolated from <Emphasis Type="Italic">Aconitum szechenyianum</Emphasis> Gay

Two napelline skeletal diterpenoid alkaloids 15-acetylsongorine, C₂₄H₃₃NO₄ I, and songoramine, C₂₂H₂₉NO₃ II, were first isolated from the roots of Aconitum Szechenyianum Gay. The crystal structures were determined by X-ray single-crystal diffraction analysis. The crystal I is the triclinic system with space group P1 having unit cell parameters of a = 9.360(8) Å, b = 11.593(9) Å, c = 11.830(16) Å, α = 113.223(15)°, β = 105.950(16)°, γ = 101.296(12)°, and Z = 2. Hydrogen bonds O–H···O and O–H···N joint the molecules into dimer. The crystal II belongs to the orthorhombic system with space group P2₁2₁2₁ having unit cell parameters of a = 8.950(2) Å, b = 13.272(3) Å, c = 15.454(4) Å and Z = 4. The O–H···O hydrogen bonding interaction links the molecule into linear chains. The distortion of rings of compound I and II were evaluated by calculation of the Cremer and Pople puckering parameters. The presence of the C–O–C bond in the compound II results in the changes of ring conformations compared with that of the compound I.